Apparatus for removing a fibrous web from a rotatable surface



Nov. 8, 1966 F. KALWAITES 3,283,366

APPARATUS FOR REMOVING A FIBRCUS WEB FROM A ROTATABLE SURFACE Filed Aug.2, 1965 4 Sheets-Sheet 1 24 1} /2 i 1 E 4/ 5:2 q

INVENTOR FPAA/K 62; 1144/75:

mmT/W i ATTORNEY F. KALWAITES Nov. 8, 1966 APPARATUS FOR REMOVING AFIBRCUS WEB FROM A ROTATABLE SURFACE Filed Aug. 2, 1965 4 Sheets-Sheet 2T'lqflh lNVENTOR Few/r K44 1444/72-5 flit m ATTORNEY 1956 F. KALWAITES3,

APPARATUS FOR REMOVING A FIBROUS WEB FROM A ROTATABLE SURFACE Filed Aug.2, 1965 4 Sheets-Sheet 5 Q" P f I III/III ,2 y m 7 INVENTOR.

AM flfanmvas BY A ATTORNEY F. KALWAITES Nov. 8, 1966 APPARATUS FORREMOVING A FIBROUS WEB FROM A RO'I'A'I'ABLE SURFACE Filed Aug. 2, 1965 4Sheets-Sheet 4 INVENTOR FRANK. KALWAITES BY flXivLlY-b ATTORNEY UnitedStates Patent M 3,283,366 APPARATUS FOR REMOVING A FIBROUS WEB FROM AROTATABLE SURFACE Frank Kalwaites, Somerville, NJ., assignor to Johnson& Johnson, a corporation of New Jersey Filed Aug. 2, 1965, Ser. No.478,027 6 Claims. (Cl. 19-106) This patent application is acontinuation-in-part of my co-pending patent application Serial Number324,602, filed November 13, 1963, now abandoned, which in turn was acontinuation-in-part of my patent application Serial Number 279,949,filed May 13, 1963, now abandoned.

The present invention relates to apparatus and methods for removingfibrous webs from rotating surfaces and more particularly is concernedwith apparatus and methods for removing fibrous webs from the rotatingdotting cylinder of a textile carding machine.

In the processing of textile-length fibers whereby they are convertedfrom naturally-occurring or syntheticallyprepared, intermatted fibrousmasses into relatively uniform fibrous textile materials, such asslivers, rovings and webs which have a generally predominant fiberorientation in the long direction thereof, the individual fibers areinitially separated and formed into a fibrous web by means of a textilecarding machine. This fibrous web, in which the individual fibers arerelatively aligned generally in the long direction of the web, is dottedor removed from the rotating dotfing cylinder of the card usually by arapidly reciprocating dofiing comb for further processing or handling,as desired or required. This rapidly reciprocating dofiing comb, havinga periodic toand-fro movement, is physically limited in its maximumspeed and in the number of reciprocations it can make and in most casesis the limiting factor on the speed of the rotating dofling cylinderwhich, having a rotational movement, normally could have a greatersurface linear speed, if it were not so limited by the dofiing comb.Thus, the dofiing comb limits the speed of the textile carding machineand is considered the limiting factor on its capacity or throughput.

Additionally, it has been determined that the reciprocating action ofthe teeth of the doffing comb, as they rapidly pass to-and-fro throughthe fibrous Web, strike, rub and brush against the individual fibers,change the predominant fiber orientation thereof, and perform theirdotfing function in a generally ineflicient manner.

It is therefore a principal purpose of the present invention to provideapparatus and methods capable of: (1) dofiing or removing fibrousmaterials from a rotating surface such as the dofiing cylinder of atextile carding machine without limiting its speed, capacity orthroughput; and (2) performing such dofiing or fiber-removing functionin an efiicient manner without materially changing the predominant fiberorientation of the fibrous Web.

It has been discovered that such a principal purpose may be accomplishedby providing a first rotatable surface which is capable of carrying afibrous web, positioning a second rotatable surface also capable ofcarrying a fibrous web immediately adjacent to but spaced from saidfirst-mentioned rotatable surface whereby a V-shaped throat havingarcuate surfaces leading to a narrowopening is formed between the tworotatable surfaces, and then positioning a stationary but adjustableflexible nip blade in tangential pressing contact with the secondrotatable surface and extending away from that second rotatable surfaceon both sides of the point of tangency therewith, with one relativelyshort free end of the nip blade extending up into the narrow V-shapedthroat formed by the two rotatable surfaces. As a result, the fibrousWeb which is carried by the first rotatable surface can be removed3,283,366 Patented Nov. 8, 1966 ICC therefrom to be carried around thefree end of the nip blade into contact with the second rotatable surfaceto be pressed against such second rotatable surface by the nip bladesubstantially only at the point of tangency and then to be carriedforwardly by the second rotatable surface and delivered for furtherprocessing and handling, as desired or required.

Now, inasmuch as only rotating surfaces are involved in such anarrangement and since there is no limiting reciprocat-ing to-and-froperiodic movement, much higher speeds are obtainable whereby increasedcapacity or throughput is realized. Also, there is no rapidreciprocation of comb teeth to-and-fro through the fibrous web wherebyincreased doffing efficiency is realized and the predominant fiberorientation is not materially changed.

The fibrous web .or layer which is processed to form the products ofthis invention may contain natural or synthetic, vegetable, animal ormineral fibers such as cotton, silk, wool, vicuna, mohair, alpaca, flax,ramie, jute, etc.; synthetic or man-made fibers such as the cellulosicfibers, notably cuprammonium, viscose or regenerated cellulose fibers;cross-linked cellulosic fibers such as Corval and Topel; cellulose esterfibers such as cellulose acetate (Celanese) and cellulose tri-acetate(Arnel); the saponified cellulose ester fibers such as Fortisan andFortisan-36; the polyamide fibers such as nylon 420, nylon 6(polycaprolactam), nylon 66 (hexamethylene diamine-adipic acid), nylon610 (hexamethylene diaminesebacic acid), nylon 11 (ll-amino undecanoicacid-Rilsan); protein fibers such as Vicara; halogenated hydrocarbonfibers such as Tefion (polytetrafluoroethylene); hydrocarbon fibers suchas polyethylene, polypropylene, polybutadiene and polyisobutylene;polyester fibers such as Kodel and Dacron; vinyl fibers such as Vinyonand saran; dinitrile fibers such as Darvan; nitrile fibers such asZefran; acrylic fibers such as Dynel, Verel, Orlon, Acrilan, Creslan,etc.; mineral fibers such as glass, metal; etc.

The average lengths of the fibers in the starting fibrous web are oftextile length and may vary from about inch or /2 inch up to about 2 /2inches or more in length,-

depending upon the particular properties and characteristics required ordesired in the resulting fibrous web.

If desired, the fibrous layer may have added thereto, by a subsequentprocessing step, from about 1 or 2 percent by weight up to about percentby Weight but preferably less than about 50 percent by Weight, of fibersother than those of textile length. These other fibers may be of shortpapermaking length, which extend from about inch in length down to aboutof an inch or less in length, which shorter fibers normally are not usedin conventional methods of producing fibrous webs.

Illustrative of these short papermaking fibers are the naturalcellulosic fibers such as woodpulp and wood fibers, cotton linters,cotton hull shaving fibers, mineral fibers such as asbestos, glass, rockwool, etc., or any of the hereinbefore-amentioned natural or syntheticfibers in lengths less than about inch and down to about of an inch orless.

The denier of the individual synthetic fibers referred to above ispreferably in the range of the approximate thickness of the naturalfibers mentioned and consequently deniers in the range of from about 1to about 5 are preferred. Where greater opacity or greate covering poweris desired, special fiber deniers of down to about or even about /2 maybe employed. Where desired, deniers of up to about 5.5, 6, 8, 10, 15, orhigher, may be used. The minimum and maximum denier are naturallydictated by the desires or requirements for producing a particularfibrous web, by the machines and methods for producing the same, and soforth.

The weight of the fibrous web or layer of starting material on thedofling cylinder may be varied within relatively wide limits above apredetermined minimum value, depending upon the requirements oftheintermediate or the final products. A single, thin web of fibers, suchas produced by a card and as presented by the dotting cylinder, may havea weight of from about 30 to about 250 or more grains per square yardand may be used in the application of the principles of the presentinvention. Within the more commercial aspects of the present invention,however, web weights on the doffing cylinder of from about 50 grains persquare yard to about 175 grains per square yard are contemplated.

The invention will be more fully understood from the description whichfollows taken in conjunction with the accompanying drawings in whichthere are illustrated preferred designs of machines and modes ofoperation embodying the invention. It is to be understood, however, thatthe invention is not to be considered limited to the constructionsdisclosed except as determined by the scope of the appended claims. Inthe drawings:

, FIGURE 1 is a simplified, fragmentary, schematic view in elevationshowing one embodiment of the general principles of operation of thepresent invention;

FIGURE 2 is an enlarged view of a portion of FIG- URE l, drawn to a muchlarger scale showing in greater detail certain elements of the presentinvention;

FIGURE 3 is a simplified, fragmentary, schematic view in elevationshowing another embodiment of the general principles of operation of thepresent invention;

FIGURE 4 is a simplified, fragmentary, schematic view .in elevationshowing still another embodiment of the genenal principles of operationof the present'invention; and

FIGURES is a simplified, fragmentary, schematic view in elevationshowing a further embodiment of the. general principles of operation ofthe present invention; and

FIGURE dis a simplified, fragmentary, 'schematic'view in elevationshowing a further embodiment of the general principles of operation ofthe present invention.

In the embodiment of the invention illustrated in FIG- URE 1 ofthedrawing, a conventional textile card is used and comprises aconventional rotatable main'card cylinder (not shown) which is. used toprovide for the normal carding of the fibers fed thereto leadinggenerally to a thin sheet of individualized fibers very sparsely spreadover the main card cylinder surface in an amount weighing merely a few.grains per square yard. These substantially individualized fibers arethen presented to and transferred to a slower moving doffing cylinderrotating on a shaft mounted in bearings secured to the card frame 12.

The dofling cylinder 10 is convent-ional and may be covered withconventional fillets which are continuous stn'ps of narrow cardclothing, 1 /2 or 2 inches wide, and long enough to helically wraparound and entirely cover the cylindrical surface of the doffingcylinder. The conventional bent wires penetrate the heavy fabricfoundation of the fillet card clothing and protrude therefrom in theusual 'way whereby dolfing and stripping functions are possible. Ifdesired, however, the dofiing cylinder may be covered with conventionalmetallic card clothing which consists of a steel band with teethpunched-or otherwise formed in one side and usually a thick rib on theother side. This steel band is wound helically around the surface of thecylinder, on edge, so that each coil fits closely against the precedingcoil, thus producing a cylindrical surface entirely coveredwith finesaw-tooth points whereby dofiing and stripping functions are possible.

Immediately adjacent the dofling cylinder 10, and approximately at theposition where the fibrous web W formed thereon is conventionallyremoved by the usual reciprocating doffing comb, there is located acylindrical, rotatable dofiing roll 14 rotating on a shaft 18 alsomount- .ed in the card frame 12. This doffing roll 14 has about the samelength as the dofiing cylinder 10 but has a much 4. smaller diameterwhich is in the range of from about 1% inches to about 10 inches, oreven larger, but preferably is in the range of from about 3 inches toabout 6 inches. Under normal circumstances, it rotates with the samesurface linear speed as that of the dofiing cylinder 10.

The dotting roll 14 is so positioned with respect tothe dofiing cylinder10 and is so spaced therefrom that a V- shaped throat is formed betweentwo rotatable surfaces leading to a relatively narrow opening. Thisopening or clearance is sufficient to permit rotation of the doffingcylinder 10 without rubbing against the dofiing roll 14. The clearancebetween the doffing cylinder 10 and the dofiing roll 14 will depend uponmany factors such as the type of fibers being processed, the weight ofthe web being handled, the relative speeds involved, etc. In most cases,this clearance isof the order of from about 4 inch up to about inch,with a preferred range of from about inch up to about A inch.

The. dofling roll 14 is relatively smooth-faced, as cornpared to thedofling cylinder 10 which is covered with fillet or metallic cardclothing. The doffing roll 14 is given a very slightly roughened ortextured surface, preferably by means of flutes, fine knurling,engraving, etching, or sandblasting. In many instances, a texturedsurface having very small cavities, such as prevails in the case of natural or synthetic rubber, leather or like-leather surfaces is suitable.In other instances flutes running along the axis of the rolls arepreferred, for example from about 10 to 16 flutes per circumferentialinch with the flutes having a depth of from about 0.02 to 0.05 inch havebeen found suitable. on a slight spiral to the longitudinaLaxis of theroll to provide for smooth riding of thenip blade 20 and preventchattering of the blade. The fluted rolls have been found very desirablewhen dofling cotton fibers as the seed and trash material normally foundwith cotton will ride in the flutes and still allow-good contact betweenthe roll surface and the nip blade. Dofling rolls which have smooth orslick surfaces are not generally suited for the application of the basicprinciples of the present invention.

A relatively flat flexible nip blade 20 is adjustably positioned on apivot 24 and is capable of being placed in pressing tangential contactwith the dofiing roll 14. Any suitable pressure-applying means, such asa helical spring 26, may be employed to cause the nip blade 20 to exertthe desired pressure on the doffing roll 14. If desired, the flexiblenip blade 20 may merely be placed in pressing contact with the dofiingroll 14 and lockedin that position. As shown in FIGURE 1, both-sides ofthe nip blade 20 extend tangentially'away from the surface of thedofiing roll 14, with the relatively short free end 28: ex-

tending forwardly up into the V-shaped throat formed by' the dofiingcylinder 10 and dofiing roll 14. The point of tangency of the nip blade20 and the doffing roll114 is so located that the free end 28 of the nip.blade 20 is of relatively short length, and is only about A; of an inchup to about of an inch in length. As a result'of this extension of thefree end 28, a relatively short entrance opening is formed between theshort free end 28 and the surface of the doffing roll 14. The purpose ofthis small opening will be discussed hereinafter. T

The other end or the base portion 22 of the nip blade 20 also extendstangentially away from the surface of the doffing roll 14 and providesan exit opening of rapidly increasing size. The purpose of this exitopening of rapidly increasing size will also be discussed hereinafter.

Consideration of FIGURE 1 will reveal that the fibrous web W is carriedforwardly on the surface of the dofiing cylinder 10 and is directedaround the extending free end 28 of the nip blade 20 into the smallopening or entrance formed by the free end 28 and the doffing roll 14.The fibrous web W is then pressed by the nip blade 20 against thedoffing roll 14 for a very short length lo.

cated substantially at the point of tangency. Then, due to the exitopening of rapidly increasing size, the pressure It'is desired that theflutes be positioned V on the fibrous Web W is quickly released wherebyit does not build up to accumulate or drag on the dotting roll 14 but israpidly carried forwardly by any advancing means, such as a pair ofrotatably driven nip rolls 30 and 32 mounted on shafts 34 and 36rotatably mounted in bearings in the card frame. The fibrous web W isthen advanced for further process or handling, as desired or required.

FIGURE 2 is an enlarged view of the area of the dotfing roll 14immediately adjacent to its point of tangency with nip blade 20. Thisfigure illustrates the action on the fibrous web W by the nip blade 20and the dofiing roll 14. The relatively short area of pressing contactis to be noted particularly whereby the possibility of frictional dragon the fibrous web is drastically reduced, thus decreasing thepossibility of jamming and fiber accumulation on-the dofling roll 14. Ifthe area of pressing contact becomes too large or too long, fiberaccumulation and machine stoppages will occur.

Also illustrated in FIGURE 2 is (1) the common tangent line which passestangentially between the .doffing cylinder and the dofiing roll 14 and(2) the common center line passing through the centers of the doffin-gcylinder 10 and the dotfing roll 14. These lines are, of course, atright angles to each other. The nip blade 20 is so inclined that itsangular relationship with respect to the common tangent line is in therange of from 10 to about 35, with the preferred range extending fromabout to about 30. This angle is represented by the angle a in FIGURE 2,and, due to the geometric relationship involved, is also the anglebetween the common center line and a radius of the dofiing roll 14 whichgoes to the point of tangency of the dofling roll 14 and the nip blade20.

In FIGURE 3 there is illustrated another embodiment of the presentinvention wherein corresponding parts are given reference numerals 30higher than their counterparts in FIGURE 1. The basic difference in thetwo embodiments is the use of a curved or arcuate nip blade 50 in thisembodiment, as compared to the relatively planar or flat nip blade usedin the embodiment of FIGURE 1. The use of such a curved nip blade 50which is convexly shaped with respect to the rotating surface of thedofiing roll 44 permits a wider entrance opening with a shorter free end58 as well as an exit opening with an' even more rapid increase in sizefor the same length of the base portion 52 of the nip blade 50.Naturally, the length of the area of tangency is also decreased which ishighly desirable.

In the embodiment of the invention illustrated in FIG- URES l and 3,relatively smooth-faced dolfing rolls 14 and 44 have been illustratedbut it is not essential that the doffing rolls be relativelysmooth-faced. As shown in FIGURE 4 wherein corresponding parts are givenreference numerals 60 higher than their counterparts in FIGURE 1, adofiing cylinder 7 0 cooperates with a rotatable dofling roll 74 whichis mounted on a shaft 78 secured in bearings in the card frame 72. Asillustrated in FIGURE 4, the dofiing roll 74 is provided with aperipheral surface having wire teeth 75 extending thereon. Such wireteeth may be either conventional fillets or metallic card clothing, asdesired. Plush or pile fabric surfaces may also be used.

The dofiing roll 74 is illustrated adjacent to and spaced from'thedofiing roll 70 in very much the same relationship which exists betweendofiing roll 14 and doffing cylinder 10. FIGURE 4 also illustratesanother variation of the embodiment disclosed in FIGURES 1 and 3 in thatthe direction of rotation of the dofling roll 74 is opposite to thedirection of rotation of the dofling roll 70. Additionally, it is alsoto be noted that the flexible nip blade 80, which is mounted on pivot 84and is provided with a helical spring 86, a free end 88 and a baseportion 82, is located on the opposite side of the point of closestadjacency of the dotling roll 74 and the dofling cylinder 70. As such,there is also provided an oppositely di- 6 rected V-shaped throat havingarcuate sides leading to a narrow opening or clearance, as previouslydescribed.

The operation of the apparatus illustrated in FIGURE 4 is generallysimilar in principle to the forms of apparatus illustrated in FIGURES 1and 3. Specifically, the fibrous web W" is carried forwardly on thesurface of the dofiing cylinder 70, passes through the narrow opening orclearance, and is then directed under the short free end 88 of the nipblade 80. The fibrous web W is then pressed against the dofling roll 74by the flexible nip blade substantially only at the point of tangencyand is then carried forwardly on the surface of the dofi'ing roll 74 tobe drawn forwardly by a pair of rotatable nip rolls and 92 mounted onshaft 94 and 96 secured in hearings in the card frame 72. The web W" isthen forwarded for further processing or handling, as desired orrequired.

It is not essential that the two rotatable surfaces used in theapplication of the principles of the present invention be a doffingcylinder and a dofiing roll. In FIGURE 5, there is illustrated a furtherembodiment of the present invention wherein a conventional main cylinder98 and a conventional dofling cylinder 100 are employed, along with adoffing roll 104 and its associated nip blade 112.

The operation of the apparatus illustrated in FIGURE 5 is basicallysimilar in principle to that of the other forms of apparatus illustratedin FIGURES l, 3 and 4. Specifically, a fibrous web W is carriedforwardly on the peripheral surface of the main cylinder 98 and iscarded by the card flats (not shown). The fibrous web passes downwardlybetween the nip or throat formed by the surfaces of the main cylinder 98and the dofling cylinder 100 and is then directed under the short freeend of a flexible nip blade 102 positioned in light-pressing, tangentialcontact with the peripheral surface of the dofling cylinder 100 in verymuch the same fashion as the nip blade 22 in FIGURES 1 and 2 ispositioned with respect to dofiing roll 14 and doffing cylinder 10therein.

The fibrous web is then lightly pressed against the dot]?- ing cylinder100 by the flexible nip blade 142 substantially only at the point oftangency and is then carried forwardly on the peripheral surface of thedoffing cylinder 100 and removed therefrom subsequently by dofling roll104 and associated nip blade 112, or by any other desired doffing means,such as a dofiing comb, for example. The fibrous web may then beforwarded for further processing or handling, as desired or required;

An adjustable nip blade assembly 144 is employed to properly positionthe nip blade 142 and comprises a rotatable andadjustable base 146provided with an adjustable screw mounting 148, The nip blade 142 issecured to the base 146 by any desired securing means.

In FIGURE 6 there is illustrated another embodiment of the presentinvention. A conventional dofling cylinder covered with conventionalclothing either fillet or metallic is provided and rotates in thedirection of the arrow shown. Mounted on a frame 161 immediatelyadjacent the dofi'ing cylinder is the dofiing roll 162. The dofiing rollis mounted for rotation on the shaft 163 mounted in the frame androtates in the direction of the arrow shown. The doffing roll has flutes164 on its outer surface. There are approximately 16 flutes percircumferential inch of the roll and the flutes have a depth of about0.035 inch. The flutes run in the longitudinal direction of the roll ona slight spiral of about 1%,- inches.

A flexible nip blade 165 is adjustably positioned on pivot 166 mountedfrom the frame 161 and is capable of being placed in pressing tangentialcontact with the doffing roll. The nip blade is bent slightly at A toinsure a line contact on the doffing roll and removes the blade frominterfering with the fibrous web as it leaves the dofiing roll. Bothsides of the nip blade 165 extend tangentially away from the surface ofthe doffingroll 162 with the free end 167 extending forwardly up intothe V-shaped throat formed by the doffing cylinder and doff ing roll.The other end or base portion .168 extends tangentially away to the bendA. The base portion with the bend provides an exit opening of rapidlyincreasing .size.

The fibrous web F is carried forwardly on the-surface of the dofiingcylinder and is directed around the extending free end of the nip blade.The web is pressed by the nip blade against the dofiiing roll for a veryshort length cleaner roll rotates in the directionof the arrow shown-The cleaner roll is preferably felt-covered and is used to remove anyfibers which may become wrapped about the -dofling roll.

Mounted behind the cleaner roll in light contact with the dofiing rollis the brushf 174. The brush is mounted on a stationary shaft 175mounted in the frame.

The brush is used to keep the dofiing roll clean, that is, free of loosefibers.

The invention will be further illustrated in greater detail by the:following specific examples. It should be understood, however, thatalthough these examples may .describe in particular detail some of themore specific features of the invention, they are given primarily forpurposes of illustration and the invention in its broader aspects is notto be construed as limited thereto.

Example I The starting fibrous material, as positioned on the dofiingcylinder of a textile card, is a 45" wide card web of viscose rayonstaple'fibers, Weighing about 75 grains per square yard and containingfibers having a substantially uniform average length of about F7 and adenier of about 1 /2. The peripheral surface linear velocity of .thedofiing cylinder is about 20 yards per minute. 'The dofiing cylinder iscovered with metallic card clothing in FIGURE 1, and then passes betweenthe nip blade and the dotting roll which also has a peripheral surfacelinear speed of about 20 yards per minute. A helical spring positionedon the nip blade pivot exerts a slight pres- .sure against the. nipblade whereby the fibrous web is .pressed against the surface of thedofiing roll only at the point of tangency.

The dolfing roll is steel and is relatively smooth-faced, as compared tothe dotting cylinder which, as noted above, is covered with metalliccard clothing. The doff- -ing roll has a slightly roughened or texturedsurface created by sand-blasting. The finish is referred to as a satinfinish.

Immediately after such pressing action by the nip blade which takesplace substantially only at the point of tangency, the fibrous web exitsinto a rapidly diverging opening and is relatively free to be drawnforwardly by a pair of rotatable nip rolls.

Examination of the fibrous web after it has passed .through therotatable niprolls indicates that the predominant fibrous orientationhas not been materially changed.

Examples 11 and III The procedures set forth in Example I are carriedout substantially as set forth therein with'the exception that thespeeds of the dofling cylinder and the doffing roll are both increasedto (a) 30 yards per minutes and (b) 40 yards per minute.

The fiber transfer takes place with continued high efliciency andwithout disturbing the predominant fibrous orientation of the web to anysubstantial degree.

p 0 Example IV Examples V, VI and VII The procedures set forth inExample I are carried out substantially as set forth therein With theexception that the surface of the dofiing roll is slightly roughened ortextured by means of (a) fine knurling, (b) fine engraved lines, and (c)relatively fine etching. The results are comparable to those set forthin Example 1.

Although the present invention has been described with particularreference to a doffing cylinder and a doffing roll which rotate withsusbtantially the same peripheral surface linear speed, it is to beappreciated that the peripheral surface linear speed of the doffing rollneed not neces' sarily be the same as that of the dofiing cylinder. Forexample, if the peripheral surface linear speed of the dofling roll isincreased, so that it is greater than that of the dofiing cylinder,drafting of the fibers results whereby their par-allelization andalignment is improved in the long direction. In order to obtain suchdrafting of-the fibers, the ratio of the peripheral surface linear speedof the dofi'ing'roll to the peripheral surface linear speed of thedofiing cylinder should be greater than 1:1 and may be up to about 10:1,with preferred ranges being from about 1% :1 up to about 2 /2:1.

Example VIII Example IX The procedures of Example I are carried outsubstan tially as set forth therein except that a nip blade assembly asillustrated in FIGURE 5 is used to transfer the fibrous web from'themain cylinder to the doffing cylinder prior to its removal therefrom bythe doffing roll. The problems of a vanishing Web are eliminated and'theoperation is successful.

Example X The procedures of Example I are carried out substantially asset forth therein except that the peripheral sur-,

face linear velocity of the dofling roll is decreased to. (a) 15; (b)10; and (c) 7 yards per minute. The device is operative and the resultsare comparable except that a heavier, more compacted and less orientedweb is ob-- tained.

In the drawings, no driving means such as motors, pulleys, belts, gears,sprockets, and the like have been illustrated for the doffing cylinder,the doffing roll, or the pair of nip rolls. It must be understood thatthis has been I done because such driving means are conventional andwell known in the art. Additionally, their omission from the drawingsmakes the individual figures thereof less complicated and easier to readand to understand.

Although several specific examples of the inventive concept have beendescribed, the same should not be.

construed. as limited thereby nor to the specific features mentionedtherein but to include various other equivalent features as set forth inthe claims appended hereto. It is understood that any suitable changes,modifications and variations may be made Without departing from thespirit and scopcof the invention.

What is claimed is:

1. Apparatus for removing a fibrous web from a rotatable surfacecarrying the same which comprises:

a rotatable surface capable of carrying a fibrous web;

a rotatable roll capable of carrying a fibrous web and locatedimmediately adjacent said first-mentioned rotatable surface whereby aV-shaped throat is formed between the rotatable surface and the rtatableroll; and

a stationary flexible nip blade in tangential contact with saidrotatable roll and immediately extending away from said rotatable rollon both sides of the point of tangency therewith, one free end of saidnip blade extending into the throat formed by the rotatable surface andthe rotatable roll, whereby the fibrous web carried by the firstrotatable surface is removed therefrom, carried around the free end ofsaid nip blade into contact with the rotatable roll to be pressedthereagainst by the nip blade at the point of tangency and carriedforwardly by the rotatable roll.

2. Apparatus defined in claim 1 wherein the stationary nip blade isarcuate and convex with respect to the rotatable roll.

3. Apparatus defined in claim 1 wherein the rotatable roll has anengraved finish.

4. Apparatus defined in claim 1 wherein the rotatable roll is fluted.

5. Apparatus for removing a fibrous web from a retatable surfacecarrying the same which comprises:

a rotatable surface capable of carrying a fibrous web;

a rotatable roll having flutes disposed longitudinally along the surfaceof the roll and on a slight spiral capable of carrying a fibrous web andsaid rotatable roll located immediately adjacent said first-mentionedrotatable surface whereby a V-shaped throat is formed between therotatable surface and the rotatable roll; and

a stationary flexible nip blade in tangential contact with saidrotatable roll and immediately extending away from said rotatable rollon both sides of the point of tangency therewith, one free end of saidnip blade extending into the throat formed by the rotatable surface andthe rotatable roll, whereby the fibrous web carried by the rotatablesurface is removed therefrom, carried around the free end of said nipblade into contact with the rotatable roll to be pressed thereagainst bythe nip blade at the point of tangency and carried forwardly by therotatable roll.

6. Apparatus for removing a fibrous web from a rotatable surfacecarrying the same which comprises:

a rotatable surface capable of carrying a fibrous web;

a rotatable roll having from about 10 to 16 flutes per circumferentialinch disposed longitudinally along the surface of the roll and at aslight spiral to the longitudinal axis of said roll capable of carryinga fibrous web and said rotatable roll located immediately adjacent saidfirst-mentioned rotatable surface whereby a V-shaped throat is formedbetween the rotatable surface and the rotatable roll; and

a stationary flexible nip blade in tangential contact with saidrotatable roll and immediately extending away from said rotatable rollon both sides of the point of tangency therewith, one free end of saidnip blade extending into the throat formed by the rotatable surface andthe rotatable roll, whereby the fibrous web carried by the rotatablesurface is removed therefrom, carried around the free end of said nipblade into contact with the rotatable roll to be pressed thereagainst bythe nip blade at the point of tangency and carried forwardly by therotatable roll.

References Cited by the Examiner UNITED STATES PATENTS 6/1932 Laurency19-106 FOREIGN PATENTS Ad. 44,595 12/1934 France.

3,444 of 1862 Great Britain.

MERVIN STEIN, Primary Examiner.

DONALD W. PARKER, Examiner.

D. NEWTON, Assistant Examiner.

1. APPARATUS FOR REMOVING A FIBROUS WEB FROM A ROTATABLE SURFACECARRYING THE SAME WHICH COMPRISES: A ROTATABLE SURFACE CAPABLE OFCARRYING A FIBROUS WEB; A ROTATABLE ROLL CAPABLE OF CARRYING A FIBROUSWEB AND LOCATED IMMEDIATELY ADJACENT SAID FIRST-MENTIONED ROTATABLESURFACE WHEREBY A V-SHAPED THROAT IS FORMED BETWEEN THE ROTATABLESURFACE AND THE ROTATABLE ROLL; AND A STATIONARY FLEXIBLE NIP BLADE INTANGENTIAL CONTACT WITH SAID ROTATABLE ROLL AND IMMEDIATELY EXTENDINGAWAY FROM SAID ROTATABLE ROLL ON BOTH SIDES OF THE POINT OF TANGENCYTHEREWITH, ONE FREE END OF SAID NIP BLADE EXTENDING INTO THE THROATFORMED BY THE ROTATABLE SURFACE AND THE ROTATABLE ROLL, WHEREBY THEFIBROUS WEB CARRIED BY THE FIRST ROTATABLE SURFACE IS REMOVED THEREFROM,CARRIED AROUND THE FREE END OF SAID NIP BLADE INTO CONTACT WITH THEROTATABLE ROLL TO BE PRESSED THEREAGAINST BY THE NIP BLADE AT THE POINTOF TANGENCY AND CARRIED FORWARDLY BY THE ROTATABLE ROLL.